Research efforts are directed towards defining the repertoire of integrin cell adhesion receptors which are involved in neoplastic behavior in squamous cell neoplasms that affect human communication. Immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) are being used to define expression of integrins during differentiation, tumor formation, invasion and metastasis of these neoplasms. Three integrins, alpha6beta4, alpha2beta1, and alpha3beta1 are strongly expressed in a relatively larger suprabasilar population in neoplasms during the progressive acquisition of malignant potential and this expression is associated with cell proliferation. Inhibitory monoclonal antibodies and synthetic peptides are being defined that specifically inhibit attachment of squamous cell carcinoma lines to extracellular matrix in vitro. An experimental model is being developed to test the effects of promising agents upon invasion and metastasis in vivo.